Sterile medical liquids such as normal saline, 5% dextrose, sterile water, etc., are often bottled and sterilized by manufacturers and then shipped to hospitals. The bottles remain unopened until immediately ready to administer sterile irrigating liquids to a surgical wound or to give an intravenous feeding to a patient, etc.
It is highly critical to have a test to insure that the closed containers have been properly sterilized. Sterilization is often accomplished by subjecting the closed seal containers to steam autoclaving at 240.degree. to 260.degree.F (116.degree. to 127.degree.C). When the bottles are of rigid glass they are often evacuated and utilize a thin rubber disc over an opening in the container outlet as a sterility indicator. The evacuated interior of the bottle creates a visual dimple in the rubber disc for indicating the integrity of the bottle seals and sterility of the contents.
However, when a semi-rigid or collapsible thermoplastic bottle or bag is used for storing and dispensing the sterile medical liquids evacuation is not practical. Evacuation of such thermoplastic containers that have an air space above the liquid would cause such containers to collapse. Therefore it is necessary to provide an indicator that shows the bottle has been through the autoclave and also that the closure seals are intact. This invention relates to such a sterility indicator for a non-evacuated sterile medical liquid container.